import torch.nn as nn

class Logistic(nn.Module):
    def __init__(self, input_dim=2):
        super(Logistic, self).__init__()
        self.fc = nn.Linear(input_dim, 1)
        self.sigmod = nn.Sigmoid()

    def forward(self, x):
        x = self.fc(x)
        x = self.sigmod(x)
        return x.view(-1)


